A cap operating mechanism is known, in which the cap is normally biased by a spring to be opened so that the cap is opened upon depression of a push button exclusively used to open the cap and the cap is closed against the biasing force of the spring.
However, such conventional mechanism has inconveniently required quite different actions to open the cap and to close the cap, so it is possible for a user to open the cap of a container, held in his or her one hand with the same hand, but it is impossible to close the cap in this manner.